From d3835a1656ba0187a75af0b74dd3ac27b1bf2bc5 Mon Sep 17 00:00:00 2001
From: Mahmood Ali <mahmood@hashicorp.com>
Date: Wed, 28 Jul 2021 11:21:53 -0400
Subject: [PATCH] api: revert to defaulting to http/1 (#10958)

* api: revert to defaulting to http/1

PR #10778 incidentally changed the api http client to connect with
HTTP/2 first. However, the websocket libraries used in `alloc exec`
features don't handle http/2 well, and don't downgrade to http/1
gracefully.

Given that the switch is incidental, and not requested by users.
Furthermore, api consumers can opt-in to forcing http/2 by setting
custom http clients.

Fixes #10922
---
 .changelog/10958.txt | 4 ++++
 api/api.go           | 4 ++++
 2 files changed, 8 insertions(+)
 create mode 100644 .changelog/10958.txt

diff --git a/.changelog/10958.txt b/.changelog/10958.txt
new file mode 100644
index 000000000000..2f85b2a6d580
--- /dev/null
+++ b/.changelog/10958.txt
@@ -0,0 +1,4 @@
+
+```release-note:bug
+api: Reverted to using http/1 to fix a 1.1.2 regression in `alloc exec` sessions
+```
diff --git a/api/api.go b/api/api.go
index d1f985dbefe7..140089e4c793 100644
--- a/api/api.go
+++ b/api/api.go
@@ -249,6 +249,10 @@ func defaultHttpClient() *http.Client {
 		MinVersion: tls.VersionTLS12,
 	}
 
+	// Default to http/1: alloc exec/websocket aren't supported in http/2
+	// well yet: https://github.com/gorilla/websocket/issues/417
+	transport.ForceAttemptHTTP2 = false
+
 	return httpClient
 }